Panic when running t/spec/S32-io/socket-recv-vs-read.t with a small nursery

gistfile1.txt

Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff64dc700 (LWP 63446)]
1..13
[New Thread 0x7fffefd90700 (LWP 63884)]
[New Thread 0x7fffef58f700 (LWP 63887)]
[New Thread 0x7fffeeb5d700 (LWP 63897)]
[Switching to Thread 0x7fffeeb5d700 (LWP 63897)]

Thread 5 "moar" hit Breakpoint 1, MVM_panic (exitCode=1, messageFormat=0x7ffff769da48 "Collectable %p in fromspace accessed") at src/core/exceptions.c:830
830	MVM_NO_RETURN void MVM_panic(MVMint32 exitCode, const char *messageFormat, ...) {
(gdb) bt
#0  MVM_panic (exitCode=1, messageFormat=0x7ffff769da48 "Collectable %p in fromspace accessed") at src/core/exceptions.c:830
#1  0x00007ffff75222fe in push (tc=0x555558bba440, st=0x5555557d1340, root=0x7fffe4001590, data=0x7fffe40015a8, value=..., kind=8) at src/6model/reprs/VMArray.c:480
#2  0x00007ffff751934d in MVM_repr_push_o (tc=0x555558bba440, obj=0x7fffe4001590, pushee=0x55555575cfe0) at src/6model/reprconv.c:387
#3  0x00007ffff75118bd in listen_setup (tc=0x555558bba440, loop=0x555558ab4750, async_task=0x55555575d070, data=0x5555576458e0) at src/io/asyncsocket.c:801
#4  0x00007ffff75004da in setup_work (tc=0x555558bba440) at src/io/eventloop.c:18
#5  0x00007ffff7500995 in async_handler (handle=0x55555881dff0) at src/io/eventloop.c:76
#6  0x00007ffff7678779 in uv__async_io (loop=0x555558ab4750, w=<optimized out>, events=<optimized out>) at 3rdparty/libuv/src/unix/async.c:147
#7  0x00007ffff7672b61 in uv__io_poll (loop=loop@entry=0x555558ab4750, timeout=-1) at 3rdparty/libuv/src/unix/linux-core.c:384
#8  0x00007ffff76791e8 in uv_run (loop=0x555558ab4750, mode=UV_RUN_DEFAULT) at 3rdparty/libuv/src/unix/core.c:368
#9  0x00007ffff7500a06 in enter_loop (tc=0x555558bba440, callsite=0x7ffff7dd3ba0 <null_args_callsite>, args=0x0) at src/io/eventloop.c:90
#10 0x00007ffff75290f3 in invoke_handler (tc=0x555558bba440, invokee=0x55555575d190, callsite=0x7ffff7dd3ba0 <null_args_callsite>, args=0x0) at src/6model/reprs/MVMCFunction.c:9
#11 0x00007ffff74be419 in thread_initial_invoke (tc=0x555558bba440, data=0x555558b07c40) at src/core/threads.c:59
#12 0x00007ffff7475441 in MVM_interp_run (tc=0x555558bba440, initial_invoke=0x7ffff74be38e <thread_initial_invoke>, invoke_data=0x555558b07c40) at src/core/interp.c:137
#13 0x00007ffff74be4d9 in start_thread (data=0x555558b07c40) at src/core/threads.c:87
#14 0x00007ffff68f06db in start_thread (arg=0x7fffeeb5d700) at pthread_create.c:463
#15 0x00007ffff6fc788f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb) info threads
  Id   Target Id         Frame 
  1    Thread 0x7ffff7fdb740 (LWP 63315) "moar" MVM_interp_run (tc=0x555555758cc0, initial_invoke=0x7ffff762e414 <toplevel_initial_invoke>, invoke_data=0x555555815568) at src/core/interp.c:6579
  2    Thread 0x7ffff64dc700 (LWP 63446) "moar" 0x00007ffff68f69f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5555557f3334) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
  3    Thread 0x7fffefd90700 (LWP 63884) "moar" 0x00007ffff68f69f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x555558b77950) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
  4    Thread 0x7fffef58f700 (LWP 63887) "moar" 0x00007ffff6f8a9d0 in __GI___nanosleep (requested_time=0x7fffef58d490, remaining=0x7fffef58d490) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
* 5    Thread 0x7fffeeb5d700 (LWP 63897) "moar" MVM_panic (exitCode=1, messageFormat=0x7ffff769da48 "Collectable %p in fromspace accessed") at src/core/exceptions.c:830
(gdb)